Hyundai i20 Quiz
Engine Electrical System

Repair Procedures

In this manual: Engine Electrical System
General Information — 17Engine Mechanical System — 79Engine Electrical System — 50Emission Control System — 22Engine/Fuel Control System — 107Clutch System — 27MANUAL TRANSMISSION SYSTEM — 21Drive Shaft and Axle — 18Suspension System — 29Steering System — 21Restraint — 41Braking System — 53Body Work (Interior and Exterior) — 190Body Electrical System — 181Heating, Ventilation and Air Conditioning — 58
29steps
~174min
5/5difficulty
Done 0 of 29

Inspection

Inspection Item

  • Battery Performance Check
  • Battery Voltage Check
  • Charging Voltage Check
  • GENERAL INSPECTION
  • Battery Terminal Condition Check
  • Transmission/Engine Condition Check
  • Wiring Harness Ground Condition Check
  • Specified Electrical Value Check
  • Vehicle Dark Current Check
  • Battery Capacity Check
Battery Performance Check Battery Voltage Check
  1. After driving the vehicle, if 20 minutes have not elapsed since the engine was stopped, turn the ignition switch ON and activate electrical accessories (headlights, blower motor, rear window defroster, etc.) for 60 seconds to remove the surface charge.
  2. Turn the ignition switch to the OFF position and turn off the electrical systems.
  3. Measure the battery voltage between the negative (-) and positive (+) terminals.

    Standard voltage: 12.5–12.9 V [20 °C]

    If the voltage is below the specified value, charge the battery.
  4. Start the engine.
  5. Turn on the electrical systems.
  6. Maintain engine speed at 2500 rpm.
  7. Measure the battery voltage between the negative (-) and positive (+) terminals.

    Standard voltage: Approximately 13.5–14.5 V [20 °C]

    If the voltage is below the specified value, charge the battery.
  8. Make sure the battery terminals are not loose or corroded. (See Charging System - Battery)
  9. Check the continuity of the fuses. Alternator fuse
    1. Check the continuity of the alternator fuse (A).
    2. Measure the voltage as shown in the illustration below.

      STANDARD VALUE: Approximately 0 V

    3. If the alternator fuse is blown, replace it as described in the procedure below:
      K. Turn the ignition switch to the OFF position and disconnect the negative (-) battery cable.
      b. Remove the nuts securing the positive (+) battery cable (A).
      vs. Replace the alternator fuse or the battery cable.
      d. To install, perform the removal procedure in reverse order.
  10. DRIVE BELT INSPECTION
    1. Visually check the belt for excessive wear, frayed cords, etc. If any defects are found, replace the drive belt.
  11. Measure and adjust the drive belt tension. (Refer to Engine Mechanical System - "Drive Belt")
  12. Visually inspect the alternator wiring and check for any abnormal noise.
    1. Check the wiring for proper condition.
    2. With the engine running, make sure there is no abnormal noise coming from the alternator.
  13. CHARGE WARNING LAMP CIRCUIT INSPECTION
    1. Warm up the engine and then stop it.
    2. Turn off all accessories.
    3. Turn the ignition switch to the ON position. Make sure the charge warning lamp illuminates.
    4. Start the engine. Make sure the warning lamp goes out. If the lamp does not go out as specified, check for an open circuit in the charge warning lamp circuit.
Charging Voltage Check GENERAL INSPECTION Battery Terminal Condition Check

Component Location Check

1. Alternator B+ terminal
2. Engine compartment fuse and relay block positive (+) terminal
3. Battery positive (+) terminal		 4. Battery negative (-) terminal
5. Body ground

Transmission/Engine Condition CheckWiring Harness Ground Condition Check
1. Engine ground (engine ↔ frame)
2. Transmission ground (transmission ↔ body)

Specified Electrical Value Check (Using Voltmeter and Ammeter)
  1. ALTERNATOR OUTPUT CABLE VOLTAGE DROP TEST: This test determines whether the wiring between the alternator B terminal and the positive (+) battery terminal is in proper condition, using the voltage drop method.
    1. Preparation
      K. Set the ignition switch to the OFF position.
      b. Disconnect the output cable from the alternator B terminal. Connect the (+) lead of the ammeter to the alternator B terminal and the (-) lead of the ammeter to the output cable. Connect the (+) lead of the voltmeter to the alternator B terminal and the (-) lead of the voltmeter to the positive (+) battery terminal.
    2. Test
      K. Start the engine.
      b. Turn on the headlights and the blower motor, and adjust the engine speed until the ammeter reads 20 A. Read the voltmeter.
    3. RESULT
      K. The voltmeter should show the standard value.

      STANDARD VALUE: 0.2 V max.
      b. If the voltmeter reading is higher than the specified value (more than 0.2 V max.), suspect a wiring fault. In this case, check the wiring between the alternator B terminal and the positive (+) battery terminal. Check whether the connections are loose, whether discoloration from overheating exists, whether there is excess wiring, etc. Correct these items before repeating the test.
      vs. After completing this test, return the engine speed to idle. Turn off the headlights, blower motor and ignition switch.
  2. ALTERNATOR OUTPUT CURRENT TEST: This test determines whether the alternator output current is normal.
    1. Preparation
      K. Before testing, check the following items and correct if necessary. Check that the battery installed in the vehicle is in good condition. Refer to the "Battery" section for battery service. The battery used for the output current test should be partially discharged. The test cannot be performed correctly with a fully charged battery, because there is insufficient load. Check the alternator drive belt tension. Refer to "Drive Belt Inspection" to check belt tension.
      b. Turn the ignition switch to the OFF position.
      vs. Disconnect the battery ground cable.
      d. Disconnect the alternator output cable from the alternator B terminal.
      e. Connect a DC ammeter (0 to 150 A) in series between the B terminal and the disconnected output cable. Make sure the negative (-) lead of the ammeter is connected to the disconnected output cable.
      f. Connect a voltmeter (0 to 20 V) between the B terminal and ground. Connect the (+) lead to the alternator wire B terminal and the (-) lead to a proper ground.
      g. Connect the battery ground cable.
      h. Leave the engine hood open.
    2. Test
      K. Make sure the voltmeter shows the same value as the battery voltage. If the voltmeter reads zero, there is an open circuit in the cable between the alternator B terminal and the positive (+) battery terminal, or a faulty ground connection.
      b. Start the engine and turn on the headlights.
      vs. Set the headlights to high beam and turn the blower motor to HIGH. Quickly increase engine speed until it reaches 2500 rpm, and read the maximum output current shown on the ammeter.
    3. RESULT
      K. The ammeter reading should be greater than the limit value. If it is lower, even though the alternator output cable is in good condition, remove the alternator from the vehicle and test it.

      Limit value: 60% of the rated output
      b. After completing the output current test, reduce the engine speed to idle and turn the ignition switch to the OFF position.
      vs. Disconnect the negative (-) battery terminal.
      d. Remove the ammeter, voltmeter and engine tachometer.
      e. Connect the generator output cable to the "B" terminal of the generator.
      f. Connect the negative (-) battery terminal.
  3. REGULATED VOLTAGE TEST. The purpose of this test is to check that the electronic voltage regulator regulates the voltage correctly.
    1. Preparation
      K. Before testing, check the following items and correct if necessary. Make sure the battery installed in the vehicle is fully charged. Refer to the "Battery" section for battery service. Check the generator drive belt tension. Refer to "Drive Belt Inspection" to check the belt tension.
      b. Set the ignition switch to the OFF position.
      vs. Disconnect the negative (-) battery terminal.
      d. Connect a digital voltmeter between the "B" terminal of the generator and ground. Connect the (+) voltmeter lead to the "B" terminal of the generator. Connect the (-) lead to a good ground or to the (-) battery terminal.
      e. Disconnect the alternator output cable from the alternator B terminal.
      f. Connect a DC ammeter (0 to 150 A) in series between the "B" terminal and the disconnected output wire. Connect the (-) ammeter lead to the disconnected output wire.
      g. Connect the negative (-) battery terminal.
    2. Test
      K. Turn the ignition switch to the ON position and check that the voltmeter shows the following value.

      Voltage: Battery voltage

      If the voltmeter shows 0 V, there is an open circuit in the cable connecting the "B" terminal of the generator and the battery (-) terminal.
      b. Start the engine. Turn all lights and accessories off.
      vs. Run the engine at approximately 2500 rpm and read the voltmeter when the output current from the generator drops to 10 A or less.
    3. RESULT
      K. If the voltmeter reading differs from the standard value, the voltage regulator or the generator is faulty.

      Regulated voltage: 11.7 – 15.3 V
      b. If the voltmeter reading differs from the standard value, the voltage regulator or the generator is faulty.
      vs. Disconnect the negative (-) battery terminal.
      d. Remove the voltmeter and ammeter.
      e. Connect the generator output cable to the "B" terminal of the generator.
      f. Connect the negative (-) battery terminal.
  4. ALTERNATOR OUTPUT CABLE VOLTAGE DROP TEST: This test determines whether the wiring between the alternator B terminal and the positive (+) battery terminal is in proper condition, using the voltage drop method.
    1. Preparation
      K. Set the ignition switch to the OFF position.
      b. Install the current clamp between the positive (+) battery terminal and the "B" terminal of the generator.
      vs. Connect the (+) voltmeter lead to the "B" terminal of the generator and the (-) voltmeter lead to the battery (-) terminal.
    2. Test
      K. Start the engine.
      b. Turn on the headlights and the blower motor, and adjust the engine speed until the ammeter reads 20 A. Read the voltmeter.
    3. RESULT
      K. The voltmeter should show the standard value.

      STANDARD VALUE: 0.2 V max.
      b. If the voltmeter reading is higher than the specified value (more than 0.2 V max.), suspect a wiring fault. In this case, check the wiring between the alternator B terminal and the positive (+) battery terminal. Check whether the connections are loose, whether discoloration from overheating exists, whether there is excess wiring, etc. Correct these items before repeating the test.
      vs. After completing this test, return the engine speed to idle. Turn off the headlights, blower motor and ignition switch.
  5. ALTERNATOR OUTPUT CURRENT TEST: This test determines whether the alternator output current is normal.
    1. Preparation
      K. Before testing, check the following items and correct if necessary. Make sure the battery installed in the vehicle is in good condition. Refer to the "Battery" section for battery service. The battery used for the output current test should be partially discharged. The test cannot be performed correctly with a fully charged battery due to insufficient load. Check the generator drive belt tension. Refer to "Drive Belt Inspection" to check the belt tension.
      b. Turn the ignition switch to the OFF position.
      vs. Disconnect the negative (-) battery terminal.
      d. Install the current clamp between the positive (+) battery terminal and the "B" terminal of the generator.
      e. Connect a DC ammeter (0 to 150 A) in series between the B terminal and the disconnected output cable. Make sure the negative (-) lead of the ammeter is connected to the disconnected output cable.
      f. Connect a voltmeter (0 to 20 V) between the B terminal and ground. Connect the (+) lead to the alternator wire B terminal and the (-) lead to a proper ground.
      g. Connect the negative (-) battery terminal.
      h. Leave the engine hood open.
    2. Test
      K. Make sure the voltmeter shows the same value as the battery voltage. If the voltmeter reads zero, there is an open circuit in the cable between the alternator B terminal and the positive (+) battery terminal, or a faulty ground connection.
      b. Start the engine and turn on the headlights.
      vs. Set the headlights to high beam and turn the blower motor to HIGH. Quickly increase engine speed until it reaches 2500 rpm, and read the maximum output current shown on the ammeter.
    3. RESULT
      K. The ammeter reading should be greater than the limit value. If it is lower, even though the alternator output cable is in good condition, remove the alternator from the vehicle and test it.

      Limit value: 60% of the rated output
      b. After completing the output current test, reduce the engine speed to idle and turn the ignition switch to the ON position.
      vs. Disconnect the negative (-) battery terminal.
      d. Remove the ammeter, voltmeter and engine tachometer.
      e. Connect the generator output cable to the "B" terminal of the generator.
      f. Connect the negative (-) battery terminal.
  6. REGULATED VOLTAGE TEST. The purpose of this test is to check that the electronic voltage regulator regulates the voltage correctly.
    1. Preparation
      K. Before testing, check the following items and correct if necessary. Make sure the battery installed in the vehicle is fully charged. Refer to the "Battery" section for battery service. Check the generator drive belt tension. Refer to "Drive Belt Inspection" to check the belt tension.
      b. Set the ignition switch to the OFF position.
      vs. Disconnect the negative (-) battery terminal.
      d. Connect a digital voltmeter between the "B" terminal of the generator and ground. Connect the (+) voltmeter lead to the "B" terminal of the generator. Connect the (-) lead to a good ground or to the (-) battery terminal.
      e. Disconnect the alternator output cable from the alternator B terminal.
      f. Connect a DC ammeter (0 to 150 A) in series between the "B" terminal and the disconnected wire. Connect the negative (-) ammeter lead to the disconnected output wire.
      g. Connect the negative (-) battery terminal.
    2. Test
      K. Turn the ignition switch to the ON position and check that the voltmeter shows the following value.

      Voltage: Battery voltage

      If the voltmeter shows 0 V, there is an open circuit in the cable connecting the "B" terminal of the generator and the battery (-) terminal.
      b. Start the engine. Turn all lights and accessories off.
      vs. Run the engine at approximately 2500 rpm and read the voltmeter when the output current from the generator drops to 10 A or less.
    3. RESULT
      K. If the value read on the voltmeter does not match the standard value, the voltage regulator or the generator is faulty.

      Regulated voltage: 11.7 – 15.3 V
      b. If the value read on the voltmeter does not match the standard value, the voltage regulator or the generator is faulty.
      vs. Disconnect the negative (-) battery terminal.
      d. Remove the voltmeter and ammeter.
      e. Connect the generator output cable to the "B" terminal of the generator.
      f. Connect the negative (-) battery terminal.
  7. Turn off all electrical devices and turn off the ignition switch.
  8. Close all doors except the hood, then lock all doors.
    1. Disconnect the hood switch connector.
    2. Close the trunk.
    3. Close the doors or remove the door switches.
  9. Wait several minutes for the vehicle's electrical systems to go to sleep.
  10. Connect the ammeter in series with the battery negative (-) terminal and the ground cable, then carefully disconnect the cable from the battery negative (-) terminal.
  11. Read the current value on the ammeter.
    • If the dark current is higher than the limit value, check for an abnormal circuit by removing the fuses one at a time and monitoring the dark current.
    • Reconnect only the suspected parasitic dark current fuse and locate the faulty unit by disconnecting components connected to the circuit until the dark current drops below the limit value.

    Limit value (after 10-20 min.): Less than 50 mA

  12. Turn off all electrical devices and turn off the ignition switch.
  13. Close all doors except the hood, then lock all doors.
    1. Disconnect the hood switch connector.
    2. Close the trunk.
    3. Close the doors or remove the door switches.
  14. Wait several minutes for the vehicle's electrical systems to go to sleep.
  15. Install the current clamp on the battery negative (-) terminal.
  16. Read the current value on the ammeter.
    • If the dark current is higher than the limit value, check for an abnormal circuit by removing the fuses one at a time and monitoring the dark current.
    • Reconnect only the suspected parasitic dark current fuse and locate the faulty unit by disconnecting components connected to the circuit until the dark current drops below the limit value.

    Limit value (after 10-20 min.): Less than 50 mA

Specified Electrical Value Check (Using Voltmeter and Clamp-type Ammeter) Vehicle Dark Current Check [Using Ammeter] [Using Clamp-type Ammeter]

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